qmljsinterpreter.cpp

/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** Commercial Usage
**
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
**
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://qt.nokia.com/contact.
**
**************************************************************************/

#include "qmljsinterpreter.h"
#include "qmljsevaluate.h"
#include "qmljslink.h"
#include "parser/qmljsast_p.h"
#include <QtCore/QMetaObject>
#include <QtCore/QMetaProperty>
#include <QtCore/QDebug>

#ifndef NO_DECLARATIVE_BACKEND
#  include <QtDeclarative/QmlType>
#  include <QtDeclarative/QmlMetaType>
#  include <QtDeclarative/private/qmlgraphicsanchors_p.h> // ### remove me
#  include <QtDeclarative/private/qmlgraphicsrectangle_p.h> // ### remove me
#  include <QtDeclarative/private/qmlvaluetype_p.h> // ### remove me
#  include <QtDeclarative/private/qmlanimation_p.h> // ### remove me
#endif

using namespace QmlJS::Interpreter;
using namespace QmlJS::AST;

namespace {

class LookupMember: public MemberProcessor
{
    QString _name;
    const Value *_value;

    bool process(const QString &name, const Value *value)
    {
        if (_value)
            return false;

        if (name == _name) {
            _value = value;
            return false;
        }

        return true;
    }

public:
    LookupMember(const QString &name)
        : _name(name), _value(0) {}

    const Value *value() const { return _value; }

    virtual bool processProperty(const QString &name, const Value *value)
    {
        return process(name, value);
    }

    virtual bool processEnumerator(const QString &name, const Value *value)
    {
        return process(name, value);
    }

    virtual bool processSignal(const QString &name, const Value *value)
    {
        return process(name, value);
    }

    virtual bool processSlot(const QString &name, const Value *value)
    {
        return process(name, value);
    }

    virtual bool processGeneratedSlot(const QString &name, const Value *value)
    {
        return process(name, value);
    }
};

} // end of anonymous namespace

#ifndef NO_DECLARATIVE_BACKEND

namespace {

class MetaFunction: public FunctionValue
{
    QMetaMethod _method;

public:
    MetaFunction(const QMetaMethod &method, Engine *engine)
        : FunctionValue(engine), _method(method)
    {
    }

    virtual const Value *returnValue() const
    {
        return engine()->undefinedValue();
    }

    virtual int argumentCount() const
    {
        return _method.parameterNames().size();
    }

    virtual const Value *argument(int) const
    {
        return engine()->undefinedValue();
    }

    virtual QString argumentName(int index) const
    {
        if (index < _method.parameterNames().size())
            return _method.parameterNames().at(index);

        return FunctionValue::argumentName(index);
    }

    virtual bool isVariadic() const
    {
        return false;
    }

    virtual const Value *invoke(const Activation *) const
    {
        return engine()->undefinedValue();
    }
};

} // end of anonymous namespace

QmlObjectValue::QmlObjectValue(const QMetaObject *metaObject, const QString &qmlTypeName,
                               int majorVersion, int minorVersion, Engine *engine)
    : ObjectValue(engine),
      _metaObject(metaObject),
      _qmlTypeName(qmlTypeName),
      _majorVersion(majorVersion),
      _minorVersion(minorVersion)
{
    setClassName(qmlTypeName); // ### TODO: we probably need to do more than just this...
}

QmlObjectValue::~QmlObjectValue() {}

const Value *QmlObjectValue::lookupMember(const QString &name, Context *context) const
{
    return ObjectValue::lookupMember(name, context);
}

const Value *QmlObjectValue::findOrCreateSignature(int index, const QMetaMethod &method, QString *methodName) const
{
    const QString signature = QString::fromUtf8(method.signature());

    const int indexOfParen = signature.indexOf(QLatin1Char('('));
    if (indexOfParen == -1)
        return engine()->undefinedValue(); // skip it, invalid signature.

    *methodName = signature.left(indexOfParen);
    const Value *value = _metaSignature.value(index);
    if (! value) {
        value = new MetaFunction(method, engine());
        _metaSignature.insert(index, value);
    }
    return value;
}

void QmlObjectValue::processMembers(MemberProcessor *processor) const
{
    // process the meta enums
    for (int index = _metaObject->enumeratorOffset(); index < _metaObject->propertyCount(); ++index) {
        QMetaEnum e = _metaObject->enumerator(index);

        for (int i = 0; i < e.keyCount(); ++i) {
            processor->processEnumerator(QString::fromUtf8(e.key(i)), engine()->numberValue());
        }
    }

    // process the meta properties
    for (int index = 0; index < _metaObject->propertyCount(); ++index) {
        QMetaProperty prop = _metaObject->property(index);

        processor->processProperty(prop.name(), propertyValue(prop));
    }

    // process the meta methods
    for (int index = 0; index < _metaObject->methodCount(); ++index) {
        QMetaMethod method = _metaObject->method(index);
        QString methodName;
        const Value *signature = findOrCreateSignature(index, method, &methodName);

        if (method.methodType() == QMetaMethod::Slot && method.access() == QMetaMethod::Public) {
            processor->processSlot(methodName, signature);

        } else if (method.methodType() == QMetaMethod::Signal && method.access() != QMetaMethod::Private) {
            // process the signal
            processor->processSignal(methodName, signature);

            QString slotName;
            slotName += QLatin1String("on");
            slotName += methodName.at(0).toUpper();
            slotName += methodName.midRef(1);

            // process the generated slot
            processor->processGeneratedSlot(slotName, signature);
        }
    }

    ObjectValue::processMembers(processor);
}

const Value *QmlObjectValue::propertyValue(const QMetaProperty &prop) const
{
    if (QmlMetaType::isQObject(prop.userType())) {
        QmlType *qmlPropertyType = QmlMetaType::qmlType(prop.userType());

        if (qmlPropertyType && !qmlPropertyType->qmlTypeName().isEmpty()) {
            QString typeName = qmlPropertyType->qmlTypeName();
            int slashIdx = typeName.lastIndexOf(QLatin1Char('/'));
            QString package;
            if (slashIdx != -1) {
                package = typeName.left(slashIdx);
                typeName = typeName.mid(slashIdx + 1);
            }

            if (const ObjectValue *objectValue = engine()->newQmlObject(typeName, package, qmlPropertyType->majorVersion(), qmlPropertyType->minorVersion()))
                return objectValue;
        } else {
            QString typeName = QString::fromUtf8(prop.typeName());

            if (typeName.endsWith(QLatin1Char('*')))
                typeName.truncate(typeName.length() - 1);

            typeName.replace(QLatin1Char('.'), QLatin1Char('/'));

            if (const ObjectValue *objectValue = engine()->newQmlObject(typeName, "", -1, -1))  // ### we should extend this to lookup the property types in the QmlType object, instead of the QMetaProperty.
                return objectValue;
        }
    }

    const Value *value = engine()->undefinedValue();

    switch (prop.type()) {
    case QMetaType::QByteArray:
    case QMetaType::QString:
    case QMetaType::QUrl:
        value = engine()->stringValue();
        break;

    case QMetaType::Bool:
        value = engine()->booleanValue();
        break;

    case QMetaType::Int:
    case QMetaType::Float:
    case QMetaType::Double:
        value = engine()->numberValue();
        break;

    case QMetaType::QFont: {
        // ### cache
        ObjectValue *object = engine()->newObject(/*prototype =*/ 0);
        object->setProperty("family", engine()->stringValue());
        object->setProperty("weight", engine()->undefinedValue()); // ### make me an object
        object->setProperty("copitalization", engine()->undefinedValue()); // ### make me an object
        object->setProperty("bold", engine()->booleanValue());
        object->setProperty("italic", engine()->booleanValue());
        object->setProperty("underline", engine()->booleanValue());
        object->setProperty("overline", engine()->booleanValue());
        object->setProperty("strikeout", engine()->booleanValue());
        object->setProperty("pointSize", engine()->numberValue());
        object->setProperty("pixelSize", engine()->numberValue());
        object->setProperty("letterSpacing", engine()->numberValue());
        object->setProperty("wordSpacing", engine()->numberValue());
        value = object;
    } break;

    case QMetaType::QPoint:
    case QMetaType::QPointF:
    case QMetaType::QVector2D: {
        // ### cache
        ObjectValue *object = engine()->newObject(/*prototype =*/ 0);
        object->setProperty("x", engine()->numberValue());
        object->setProperty("y", engine()->numberValue());
        value = object;
    } break;

    case QMetaType::QRect:
    case QMetaType::QRectF: {
        // ### cache
        ObjectValue *object = engine()->newObject(/*prototype =*/ 0);
        object->setProperty("x", engine()->numberValue());
        object->setProperty("y", engine()->numberValue());
        object->setProperty("width", engine()->numberValue());
        object->setProperty("height", engine()->numberValue());
        value = object;
    } break;

    case QMetaType::QVector3D: {
        // ### cache
        ObjectValue *object = engine()->newObject(/*prototype =*/ 0);
        object->setProperty("x", engine()->numberValue());
        object->setProperty("y", engine()->numberValue());
        object->setProperty("z", engine()->numberValue());
        value = object;
    } break;

    default:
        break;
    } // end of switch

    const QString typeName = prop.typeName();
    if (typeName == QLatin1String("QmlGraphicsAnchorLine")) {
        ObjectValue *object = engine()->newObject(/*prototype =*/ 0);
        object->setClassName(QLatin1String("AnchorLine"));
        value = object;
    }
    if (value->asStringValue() && prop.name() == QLatin1String("easing")
            && isDerivedFrom(&QmlPropertyAnimation::staticMetaObject)) {
        value = engine()->easingCurveNameValue();
    }

    return value;
}

bool QmlObjectValue::isDerivedFrom(const QMetaObject *base) const
{
    for (const QMetaObject *iter = _metaObject; iter; iter = iter->superClass()) {
        if (iter == base)
            return true;
    }
    return false;
}

#endif

namespace {

////////////////////////////////////////////////////////////////////////////////
// constructors
////////////////////////////////////////////////////////////////////////////////
class ObjectCtor: public Function
{
public:
    ObjectCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class FunctionCtor: public Function
{
public:
    FunctionCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class ArrayCtor: public Function
{
public:
    ArrayCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class StringCtor: public Function
{
public:
    StringCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class BooleanCtor: public Function
{
public:
    BooleanCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class NumberCtor: public Function
{
public:
    NumberCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class DateCtor: public Function
{
public:
    DateCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

class RegExpCtor: public Function
{
public:
    RegExpCtor(Engine *engine);

    virtual const Value *invoke(const Activation *activation) const;
};

ObjectCtor::ObjectCtor(Engine *engine)
    : Function(engine)
{
}

FunctionCtor::FunctionCtor(Engine *engine)
    : Function(engine)
{
}

ArrayCtor::ArrayCtor(Engine *engine)
    : Function(engine)
{
}

StringCtor::StringCtor(Engine *engine)
    : Function(engine)
{
}

BooleanCtor::BooleanCtor(Engine *engine)
    : Function(engine)
{
}

NumberCtor::NumberCtor(Engine *engine)
    : Function(engine)
{
}

DateCtor::DateCtor(Engine *engine)
    : Function(engine)
{
}

RegExpCtor::RegExpCtor(Engine *engine)
    : Function(engine)
{
}

const Value *ObjectCtor::invoke(const Activation *activation) const
{
    ObjectValue *thisObject = activation->thisObject();
    if (activation->calledAsFunction())
        thisObject = engine()->newObject();

    thisObject->setClassName("Object");
    thisObject->setPrototype(engine()->objectPrototype());
    thisObject->setProperty("length", engine()->numberValue());
    return thisObject;
}

const Value *FunctionCtor::invoke(const Activation *activation) const
{
    ObjectValue *thisObject = activation->thisObject();
    if (activation->calledAsFunction())
        thisObject = engine()->newObject();

    thisObject->setClassName("Function");
    thisObject->setPrototype(engine()->functionPrototype());
    thisObject->setProperty("length", engine()->numberValue());
    return thisObject;
}

const Value *ArrayCtor::invoke(const Activation *activation) const
{
    ObjectValue *thisObject = activation->thisObject();
    if (activation->calledAsFunction())
        thisObject = engine()->newObject();

    thisObject->setClassName("Array");
    thisObject->setPrototype(engine()->arrayPrototype());
    thisObject->setProperty("length", engine()->numberValue());
    return thisObject;
}

const Value *StringCtor::invoke(const Activation *activation) const
{
    if (activation->calledAsFunction())
        return engine()->convertToString(activation->thisObject());

    ObjectValue *thisObject = activation->thisObject();
    thisObject->setClassName("String");
    thisObject->setPrototype(engine()->stringPrototype());
    thisObject->setProperty("length", engine()->numberValue());
    return thisObject;
}

const Value *BooleanCtor::invoke(const Activation *activation) const
{
    if (activation->calledAsFunction())
        return engine()->convertToBoolean(activation->thisObject());

    ObjectValue *thisObject = activation->thisObject();
    thisObject->setClassName("Boolean");
    thisObject->setPrototype(engine()->booleanPrototype());
    return thisObject;
}

const Value *NumberCtor::invoke(const Activation *activation) const
{
    if (activation->calledAsFunction())
        return engine()->convertToNumber(activation->thisObject());

    ObjectValue *thisObject = activation->thisObject();
    thisObject->setClassName("Number");
    thisObject->setPrototype(engine()->numberPrototype());
    return thisObject;
}

const Value *DateCtor::invoke(const Activation *activation) const
{
    if (activation->calledAsFunction())
        return engine()->stringValue();

    ObjectValue *thisObject = activation->thisObject();
    thisObject->setClassName("Date");
    thisObject->setPrototype(engine()->datePrototype());
    return thisObject;
}

const Value *RegExpCtor::invoke(const Activation *activation) const
{
    ObjectValue *thisObject = activation->thisObject();
    if (activation->calledAsFunction())
        thisObject = engine()->newObject();

    thisObject->setClassName("RegExp");
    thisObject->setPrototype(engine()->regexpPrototype());
    thisObject->setProperty("source", engine()->stringValue());
    thisObject->setProperty("global", engine()->booleanValue());
    thisObject->setProperty("ignoreCase", engine()->booleanValue());
    thisObject->setProperty("multiline", engine()->booleanValue());
    thisObject->setProperty("lastIndex", engine()->numberValue());
    return thisObject;
}

} // end of anonymous namespace

////////////////////////////////////////////////////////////////////////////////
// ValueVisitor
////////////////////////////////////////////////////////////////////////////////
ValueVisitor::ValueVisitor()
{
}

ValueVisitor::~ValueVisitor()
{
}

void ValueVisitor::visit(const NullValue *)
{
}

void ValueVisitor::visit(const UndefinedValue *)
{
}

void ValueVisitor::visit(const NumberValue *)
{
}

void ValueVisitor::visit(const BooleanValue *)
{
}

void ValueVisitor::visit(const StringValue *)
{
}

void ValueVisitor::visit(const ObjectValue *)
{
}

void ValueVisitor::visit(const FunctionValue *)
{
}

void ValueVisitor::visit(const Reference *)
{
}

void ValueVisitor::visit(const EasingCurveNameValue *)
{
}

////////////////////////////////////////////////////////////////////////////////
// Value
////////////////////////////////////////////////////////////////////////////////
Value::Value()
{
}

Value::~Value()
{
}

bool Value::getSourceLocation(QString *, int *, int *) const
{
    return false;
}

const NullValue *Value::asNullValue() const
{
    return 0;
}

const UndefinedValue *Value::asUndefinedValue() const
{
    return 0;
}

const NumberValue *Value::asNumberValue() const
{
    return 0;
}

const BooleanValue *Value::asBooleanValue() const
{
    return 0;
}

const StringValue *Value::asStringValue() const
{
    return 0;
}

const ObjectValue *Value::asObjectValue() const
{
    return 0;
}

const FunctionValue *Value::asFunctionValue() const
{
    return 0;
}

const Reference *Value::asReference() const
{
    return 0;
}

const EasingCurveNameValue *Value::asEasingCurveNameValue() const
{
    return 0;
}

////////////////////////////////////////////////////////////////////////////////
// Values
////////////////////////////////////////////////////////////////////////////////
const NullValue *NullValue::asNullValue() const
{
    return this;
}

void NullValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const UndefinedValue *UndefinedValue::asUndefinedValue() const
{
    return this;
}

void UndefinedValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const NumberValue *NumberValue::asNumberValue() const
{
    return this;
}

void NumberValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const BooleanValue *BooleanValue::asBooleanValue() const
{
    return this;
}

void BooleanValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const StringValue *StringValue::asStringValue() const
{
    return this;
}

void StringValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}


ScopeChain::ScopeChain()
    : globalScope(0)
    , qmlTypes(0)
{
}

void ScopeChain::QmlComponentChain::add(QList<const ObjectValue *> *list) const
{
    foreach (QmlComponentChain *parent, instantiatingComponents)
        parent->add(list);

    if (rootObject)
        list->append(rootObject);
    list->append(functionScopes);
    if (ids)
        list->append(ids);
}

void ScopeChain::update()
{
    _all.clear();

    _all += globalScope;

    foreach (QmlComponentChain *parent, qmlComponentScope.instantiatingComponents)
        parent->add(&_all);

    if (qmlComponentScope.rootObject)
        _all += qmlComponentScope.rootObject;
    _all += qmlScopeObjects;
    _all += qmlComponentScope.functionScopes;
    if (qmlComponentScope.ids)
        _all += qmlComponentScope.ids;
    if (qmlTypes)
        _all += qmlTypes;
    _all += jsScopes;
}

QList<const ObjectValue *> ScopeChain::all() const
{
    return _all;
}


Context::Context(Engine *engine)
    : _engine(engine),
      _lookupMode(JSLookup),
      _qmlScopeObjectIndex(-1),
      _qmlScopeObjectSet(false)
{
}

Context::~Context()
{
}

void Context::build(const QList<QmlJS::AST::Node *> &astPath, QmlJS::Document::Ptr doc, const QmlJS::Snapshot &snapshot)
{
    Link link(this, doc, snapshot);
    link.scopeChainAt(doc, astPath);
}

Engine *Context::engine() const
{
    return _engine;
}

const ScopeChain &Context::scopeChain() const
{
    return _scopeChain;
}

ScopeChain &Context::scopeChain()
{
    return _scopeChain;
}

Context::LookupMode Context::lookupMode() const
{
    return _lookupMode;
}

void Context::setLookupMode(LookupMode lookupMode)
{
    _lookupMode = lookupMode;
}

const ObjectValue *Context::typeEnvironment(const QmlJS::Document *doc) const
{
    return _typeEnvironments.value(doc, 0);
}

void Context::setTypeEnvironment(const QmlJS::Document *doc, const ObjectValue *typeEnvironment)
{
    _typeEnvironments[doc] = typeEnvironment;
}

const Value *Context::lookup(const QString &name)
{
    QList<const ObjectValue *> scopes = _scopeChain.all();
    for (int index = scopes.size() - 1; index != -1; --index) {
        const ObjectValue *scope = scopes.at(index);

        if (const Value *member = scope->lookupMember(name, this)) {
            if (_lookupMode == JSLookup || ! dynamic_cast<const ASTVariableReference *>(member)) {
                return member;
            }
        }
    }

    return _engine->undefinedValue();
}

const ObjectValue *Context::lookupType(const QmlJS::Document *doc, UiQualifiedId *qmlTypeName)
{
    const ObjectValue *objectValue = typeEnvironment(doc);

    for (UiQualifiedId *iter = qmlTypeName; objectValue && iter; iter = iter->next) {
        if (! iter->name)
            return 0;

        const Value *value = objectValue->property(iter->name->asString(), this);
        if (!value)
            return 0;

        objectValue = value->asObjectValue();
    }

    return objectValue;
}

const Value *Context::property(const ObjectValue *object, const QString &name) const
{
    const Properties properties = _properties.value(object);
    return properties.value(name, engine()->undefinedValue());
}

void Context::setProperty(const ObjectValue *object, const QString &name, const Value *value)
{
    _properties[object].insert(name, value);
}

Reference::Reference(Engine *engine)
    : _engine(engine)
{
    _engine->registerValue(this);
}

Reference::~Reference()
{
}

Engine *Reference::engine() const
{
    return _engine;
}

const Reference *Reference::asReference() const
{
    return this;
}

void Reference::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const Value *Reference::value(Context *) const
{
    return _engine->undefinedValue();
}

void EasingCurveNameValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

QSet<QString> EasingCurveNameValue::_curveNames;
QSet<QString> EasingCurveNameValue::curveNames()
{
    if (_curveNames.isEmpty()) {
        _curveNames = QSet<QString>()
                      << "easeLinear"
                      << "easeInQuad"
                      << "easeOutQuad"
                      << "easeInOutQuad"
                      << "easeOutInQuad"
                      << "easeInCubic"
                      << "easeOutCubic"
                      << "easeInOutCubic"
                      << "easeOutInCubic"
                      << "easeInQuart"
                      << "easeOutQuart"
                      << "easeInOutQuart"
                      << "easeOutInQuart"
                      << "easeInQuint"
                      << "easeOutQuint"
                      << "easeInOutQuint"
                      << "easeOutInQuint"
                      << "easeInSine"
                      << "easeOutSine"
                      << "easeInOutSine"
                      << "easeOutInSine"
                      << "easeInExpo"
                      << "easeOutExpo"
                      << "easeInOutExpo"
                      << "easeOutInExpo"
                      << "easeInCirc"
                      << "easeOutCirc"
                      << "easeInOutCirc"
                      << "easeOutInCirc"
                      << "easeInElastic"
                      << "easeOutElastic"
                      << "easeInOutElastic"
                      << "easeOutInElastic"
                      << "easeInBack"
                      << "easeOutBack"
                      << "easeInOutBack"
                      << "easeOutInBack"
                      << "easeInBounce"
                      << "easeOutBounce"
                      << "easeInOutBounce"
                      << "easeOutInBounce";
    }

    return _curveNames;
}

const EasingCurveNameValue *EasingCurveNameValue::asEasingCurveNameValue() const
{
    return this;
}

MemberProcessor::MemberProcessor()
{
}

MemberProcessor::~MemberProcessor()
{
}

bool MemberProcessor::processProperty(const QString &, const Value *)
{
    return true;
}

bool MemberProcessor::processEnumerator(const QString &, const Value *)
{
    return true;
}

bool MemberProcessor::processSignal(const QString &, const Value *)
{
    return true;
}

bool MemberProcessor::processSlot(const QString &, const Value *)
{
    return true;
}

bool MemberProcessor::processGeneratedSlot(const QString &, const Value *)
{
    return true;
}

ObjectValue::ObjectValue(Engine *engine)
    : _engine(engine),
      _prototype(0)
{
    engine->registerValue(this);
}

ObjectValue::~ObjectValue()
{
}

Engine *ObjectValue::engine() const
{
    return _engine;
}

QString ObjectValue::className() const
{
    return _className;
}

void ObjectValue::setClassName(const QString &className)
{
    _className = className;
}

const ObjectValue *ObjectValue::prototype(Context *context) const
{
    const ObjectValue *prototypeObject = value_cast<const ObjectValue *>(_prototype);
    if (! prototypeObject) {
        if (const Reference *prototypeReference = value_cast<const Reference *>(_prototype)) {
            prototypeObject = value_cast<const ObjectValue *>(prototypeReference->value(context));
        }
    }
    return prototypeObject;
}

void ObjectValue::setPrototype(const Value *prototype)
{
    // ### FIXME: Check for cycles.
    _prototype = prototype;
}

void ObjectValue::setProperty(const QString &name, const Value *value)
{
    _members[name] = value;
}

void ObjectValue::removeProperty(const QString &name)
{
    _members.remove(name);
}

const ObjectValue *ObjectValue::asObjectValue() const
{
    return this;
}

void ObjectValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

const Value *ObjectValue::property(const QString &name, Context *context) const
{
    return lookupMember(name, context);
}

bool ObjectValue::checkPrototype(const ObjectValue *, QSet<const ObjectValue *> *) const
{
#if 0
    const int previousSize = processed->size();
    processed->insert(this);

    if (previousSize != processed->size()) {
        if (this == proto)
            return false;

        if (prototype() && ! prototype()->checkPrototype(proto, processed))
            return false;

        return true;
    }
#endif
    return false;
}

void ObjectValue::processMembers(MemberProcessor *processor) const
{
    QHashIterator<QString, const Value *> it(_members);

    while (it.hasNext()) {
        it.next();

        if (! processor->processProperty(it.key(), it.value()))
            break;
    }
}

const Value *ObjectValue::lookupMember(const QString &name, Context *context) const
{
    if (const Value *m = _members.value(name))
        return m;
    else {
        LookupMember slowLookup(name);
        processMembers(&slowLookup);
        if (slowLookup.value())
            return slowLookup.value();
    }

    const ObjectValue *prototypeObject = prototype(context);
    if (prototypeObject) {
        if (const Value *m = prototypeObject->lookupMember(name, context))
            return m;
    }

    return 0;
}

Activation::Activation(Context *parentContext)
    : _thisObject(0),
      _calledAsFunction(true),
      _parentContext(parentContext)
{
}

Activation::~Activation()
{
}

Context *Activation::parentContext() const
{
    return _parentContext;
}

Context *Activation::context() const
{
    // ### FIXME: Real context for activations.
    return 0;
}

bool Activation::calledAsConstructor() const
{
    return ! _calledAsFunction;
}

void Activation::setCalledAsConstructor(bool calledAsConstructor)
{
    _calledAsFunction = ! calledAsConstructor;
}

bool Activation::calledAsFunction() const
{
    return _calledAsFunction;
}

void Activation::setCalledAsFunction(bool calledAsFunction)
{
    _calledAsFunction = calledAsFunction;
}

ObjectValue *Activation::thisObject() const
{
    return _thisObject;
}

void Activation::setThisObject(ObjectValue *thisObject)
{
    _thisObject = thisObject;
}

ValueList Activation::arguments() const
{
    return _arguments;
}

void Activation::setArguments(const ValueList &arguments)
{
    _arguments = arguments;
}

FunctionValue::FunctionValue(Engine *engine)
    : ObjectValue(engine)
{
}

FunctionValue::~FunctionValue()
{
}

const Value *FunctionValue::construct(const ValueList &actuals) const
{
    Activation activation;
    activation.setCalledAsConstructor(true);
    activation.setThisObject(engine()->newObject());
    activation.setArguments(actuals);
    return invoke(&activation);
}

const Value *FunctionValue::call(const ValueList &actuals) const
{
    Activation activation;
    activation.setCalledAsFunction(true);
    activation.setThisObject(engine()->globalObject()); // ### FIXME: it should be `null'
    activation.setArguments(actuals);
    return invoke(&activation);
}

const Value *FunctionValue::call(const ObjectValue *thisObject, const ValueList &actuals) const
{
    Activation activation;
    activation.setCalledAsFunction(true);
    activation.setThisObject(const_cast<ObjectValue *>(thisObject)); // ### FIXME: remove the const_cast
    activation.setArguments(actuals);
    return invoke(&activation);
}

const Value *FunctionValue::returnValue() const
{
    return engine()->undefinedValue();
}

int FunctionValue::argumentCount() const
{
    return 0;
}

const Value *FunctionValue::argument(int) const
{
    return engine()->undefinedValue();
}

QString FunctionValue::argumentName(int index) const
{
    return QString::fromLatin1("arg%1").arg(index + 1);
}

bool FunctionValue::isVariadic() const
{
    return true;
}

const Value *FunctionValue::invoke(const Activation *activation) const
{
    return activation->thisObject(); // ### FIXME: it should return undefined
}

const FunctionValue *FunctionValue::asFunctionValue() const
{
    return this;
}

void FunctionValue::accept(ValueVisitor *visitor) const
{
    visitor->visit(this);
}

Function::Function(Engine *engine)
    : FunctionValue(engine), _returnValue(0)
{
    setClassName("Function");
}

Function::~Function()
{
}

void Function::addArgument(const Value *argument)
{
    _arguments.push_back(argument);
}

const Value *Function::returnValue() const
{
    return _returnValue;
}

void Function::setReturnValue(const Value *returnValue)
{
    _returnValue = returnValue;
}

int Function::argumentCount() const
{
    return _arguments.size();
}

const Value *Function::argument(int index) const
{
    return _arguments.at(index);
}

const Value *Function::property(const QString &name, Context *context) const
{
    if (name == "length")
        return engine()->numberValue();

    return FunctionValue::property(name, context);
}

const Value *Function::invoke(const Activation *activation) const
{
    return activation->thisObject(); // ### FIXME it should return undefined
}

////////////////////////////////////////////////////////////////////////////////
// typing environment
////////////////////////////////////////////////////////////////////////////////
ConvertToNumber::ConvertToNumber(Engine *engine)
    : _engine(engine), _result(0)
{
}

const Value *ConvertToNumber::operator()(const Value *value)
{
    const Value *previousValue = switchResult(0);

    if (value)
        value->accept(this);

    return switchResult(previousValue);
}

const Value *ConvertToNumber::switchResult(const Value *value)
{
    const Value *previousResult = _result;
    _result = value;
    return previousResult;
}

void ConvertToNumber::visit(const NullValue *)
{
    _result = _engine->numberValue();
}

void ConvertToNumber::visit(const UndefinedValue *)
{
    _result = _engine->numberValue();
}

void ConvertToNumber::visit(const NumberValue *value)
{
    _result = value;
}

void ConvertToNumber::visit(const BooleanValue *)
{
    _result = _engine->numberValue();
}

void ConvertToNumber::visit(const StringValue *)
{
    _result = _engine->numberValue();
}

void ConvertToNumber::visit(const ObjectValue *object)
{
    if (const FunctionValue *valueOfMember = value_cast<const FunctionValue *>(object->lookupMember("valueOf", 0))) {
        _result = value_cast<const NumberValue *>(valueOfMember->call(object)); // ### invoke convert-to-number?
    }
}

void ConvertToNumber::visit(const FunctionValue *object)
{
    if (const FunctionValue *valueOfMember = value_cast<const FunctionValue *>(object->lookupMember("valueOf", 0))) {
        _result = value_cast<const NumberValue *>(valueOfMember->call(object)); // ### invoke convert-to-number?
    }
}

ConvertToString::ConvertToString(Engine *engine)
    : _engine(engine), _result(0)
{
}

const Value *ConvertToString::operator()(const Value *value)
{
    const Value *previousValue = switchResult(0);

    if (value)
        value->accept(this);

    return switchResult(previousValue);
}

const Value *ConvertToString::switchResult(const Value *value)
{
    const Value *previousResult = _result;
    _result = value;
    return previousResult;
}

void ConvertToString::visit(const NullValue *)
{
    _result = _engine->stringValue();
}

void ConvertToString::visit(const UndefinedValue *)
{
    _result = _engine->stringValue();
}

void ConvertToString::visit(const NumberValue *)
{
    _result = _engine->stringValue();
}

void ConvertToString::visit(const BooleanValue *)
{
    _result = _engine->stringValue();
}

void ConvertToString::visit(const StringValue *value)
{
    _result = value;
}

void ConvertToString::visit(const ObjectValue *object)
{
    if (const FunctionValue *toStringMember = value_cast<const FunctionValue *>(object->lookupMember("toString", 0))) {
        _result = value_cast<const StringValue *>(toStringMember->call(object)); // ### invoke convert-to-string?
    }
}

void ConvertToString::visit(const FunctionValue *object)
{
    if (const FunctionValue *toStringMember = value_cast<const FunctionValue *>(object->lookupMember("toString", 0))) {
        _result = value_cast<const StringValue *>(toStringMember->call(object)); // ### invoke convert-to-string?
    }
}

ConvertToObject::ConvertToObject(Engine *engine)
    : _engine(engine), _result(0)
{
}

const Value *ConvertToObject::operator()(const Value *value)
{
    const Value *previousValue = switchResult(0);

    if (value)
        value->accept(this);

    return switchResult(previousValue);
}

const Value *ConvertToObject::switchResult(const Value *value)
{
    const Value *previousResult = _result;
    _result = value;
    return previousResult;
}

void ConvertToObject::visit(const NullValue *value)
{
    _result = value;
}

void ConvertToObject::visit(const UndefinedValue *)
{
    _result = _engine->nullValue();
}

void ConvertToObject::visit(const NumberValue *value)
{
    ValueList actuals;
    actuals.append(value);
    _result = _engine->numberCtor()->construct(actuals);
}

void ConvertToObject::visit(const BooleanValue *value)
{
    ValueList actuals;
    actuals.append(value);
    _result = _engine->booleanCtor()->construct(actuals);
}

void ConvertToObject::visit(const StringValue *value)
{
    ValueList actuals;
    actuals.append(value);
    _result = _engine->stringCtor()->construct(actuals);
}

void ConvertToObject::visit(const ObjectValue *object)
{
    _result = object;
}

void ConvertToObject::visit(const FunctionValue *object)
{
    _result = object;
}

QString TypeId::operator()(const Value *value)
{
    _result = QLatin1String("unknown");

    if (value)
        value->accept(this);

    return _result;
}

void TypeId::visit(const NullValue *)
{
    _result = QLatin1String("null");
}

void TypeId::visit(const UndefinedValue *)
{